Quade Cooper is set to make his boxing debut on Sonny Bill Williams' undercard. Source: The Sunday Mail (Qld)

QUADE Cooper will quit Australian rugby to pursue other sporting interests - starting with a debut boxing appearance on Sonny Bill Williams' undercard.

Cooper's shock switch to the sweet science is expected to be confirmed at a press conference early next week, in which he will formally announce his exit from Australian rugby and bring a temporary end to a remarkable international career of highs and lows.

The 24-year-old is so disillusioned with the ARU that he is walking away despite having signed a three-year extension with the Queensland Reds in June.

The ARU offered Cooper a highly downgraded contract with no top-up, which effectively meant he was no longer viewed as among the top 30 players in the country.

So beyond the Reds deal, Cooper was essentially being offered only match payments if he was to play for the Wallabies - a pay cut of around $200,000.

That and the recent record fine of $60,000 ($20,000 suspended) imposed upon Cooper by the ARU for his public criticism of what he described as a "toxic environment" within the Wallabies camp has left him searching for a new direction.

The 24-year-old is so disillusioned with the ARU that he is walking away despite having signed a three-year extension with the Reds in June.

The ARU offered Cooper a downgraded contract with no top-up, which effectively meant he was no longer viewed as among the top 30 players.

So beyond the Reds deal, Cooper was essentially being offered only match payments to play for the Wallabies - a pay cut of about $200,000.

That and the record fine of $60,000 ($20,000 suspended) imposed upon Cooper for his criticism of what he described as a "toxic environment" within the Wallabies has left him searching for a new direction.

Wallabies captain Nathan Sharpe last night said he was disappointed to hear the news.

Speaking in Florence, where the Wallabies are based ahead of their Test against Italy on Sunday, Sharpe said the potential loss of a gifted player like Cooper was unfortunate.

"Quade is a very talented player," Sharpe said. "I suppose people have to make their decisions. It is an individual thing for the individual.

"I don't know too much about it but it is disappointing to hear. The more players you have like that in Australia, the better. But sometimes the chips don't fall where you want them to."

European and Japanese rugby, or a code switch to the NRL, will be explored in coming days as potential avenues for Cooper.

But it is boxing where he looks set to make his next sporting appearance. It is expected Cooper and Williams will front a press conference at the Brisbane Entertainment Centre next week to announce the details of the fight, slated for late February. Williams will take on Francois Botha of South Africa.

Cooper has already begun sparring sessions and has spoken of his newly found passion for the sport.

The ARU and the Reds said last night they had not been contacted by Cooper or his management regarding any decision.

Cooper's manager Khoder Nasser also would not comment on whether Cooper was quitting Australian rugby.

Minutes after a report aired stating he was quitting last night, Cooper took to Twitter.

But instead of issuing a denial, he posted a photo of himself and Mike Tyson.

Interestingly, late yesterday Cooper's player profile was deleted from the Wallabies' website.

Williams, who returns to the NRL for the Roosters next year, recently backed Cooper to make a successful switch to league.

"If people are saying he is not wanted in rugby, first off I think they are crazy and don't know what they're talking about," Williams said.

"But if they think he is not good enough to be playing for Australia then I would love to lure him across to rugby league for a year.

"I will try. I would definitely love to play alongside him. I think he would be a success."

The Dragons last night ruled themselves out of the race for Cooper.

Coach Steve Price said: d"No one has contacted us about Quade and I'm comfortable with the halves that we have.''

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